Aortic Dissection 

 

 

Considerations

 

  • Type & urgency:

    • Stanford type A: Surgical management

    • Stanford type B: Medical management or stent only if organ damage or complicated aortic dissection

  • End organ damage & ischemia

    • Stanford type A associated with aortic insufficiency, tamponade, MI, CVA

    • Acute renal failure 

    • Spinal cord ischemia

    • Ischemic gut

    • Limb ischemia

    • Hemorrhagic shock 

    • Pleural effusions

    • Retroperitoneal bleeding 

  • Underlying cause of aortic dissection

    • Trauma 

    • Hypertension, atherosclerosis

    • Cocaine/amphetamine use

    • Pregnancy

    • Collagen vascular disease (e.g. Marfan's)

 

 

Anesthetic Management 

 

  • Medical stabilization:

    • IV access, CVC, arterial line (R arm AND L arm or femoral)

    • Hemodynamic goals 

      • ​Preload: maintain adequate preload; aggressive fluid therapy may worsen dissection 

      • Rate: heart rate <60bpm with beta blockade

      • Rhythm: maintain normal sinus rhythm

      • Contractility: reduce contractility with beta blockade to reduce sheer stress on intima 

      • Afterload: reduce sBP to a target of 100-120 mmHg to reduce sheer stress on intima 

    • Main goal is to ↓ cardiac contractility & BP to ↓ intimal stress 

      • 1st line therapy is beta blockade to achieve hemodynamic goals 

        • Labetalol (bolus 20-80mg then infusion 0.5-2mg/min) 

        • Esmolol (bolus 0.5-1 mg/kg then infusion 50-200 mcg/kg/min)

        • Consider diltiazem (2.5-5mg IV q15min) & verapamil (2.5-5mg IV q15min) in patients intolerant of beta blockers 

        • Consider adding sodium nitroprusside (0.25-0.5mcg/kg/min) to achieve sBP of 100-120mmHg

        • Adequate pain control

  • Things to avoid:

    • Inotropes

    • Hydralazine, which can cause aortic wall sheer stress

    • Vasodilation before beta blockade, which can cause reflex sympathetic activation 

    • Pericardiocentesis in tamponade, which can cause exsanguination 

 

 

Pregnancy Considerations 

 

  • Aggressive alpha & beta-blockade to ↓ dP/dT as above

  • Continuous fetal heart rate monitoring (marker of end organ perfusion)

  • Type B:

    • Medical management & expedite delivery

    • Use short acting agents (esmolol, labetalol, phentolamine)

    • Conflicts: 

      • Antihypertensives vs. bleeding risk/post partum hemorrhage (eg. nitroglycerine & ↓ uterine tone)

      • Avoid fetal toxic medications (sodium nitroprusside)

      • Avoid ergotamine for post partum hemorrhage 

  • Type A:

    • If diagnosed <28 weeks = surgical repair, then allow pregnancy to continue

    • 28-32 weeks = surgical repair, cesarean section if obstetrical indications

    • >32 weeks = simultaneous repair & cesarean section